Those that follow the legal cannabis industry are undoubtedly aware of the struggles of Colorado to regulate pesticide use on cannabis. At the time of this writing, there have been 19 recalls of products contaminated by pesticides in as many weeks. Authorities could not in all cases identify exactly how many units of products may have been tainted, but based on the numbers available, roughly 200,000 individual cannabis products, if not more, have been pulled from dispensary shelves. Along with these recalls have come a large amount of coverage and commentary from various news outlets, industry stakeholders, and even those companies who have had products pulled from shelves.

As this is a controversial and contentious subject, it can be difficult to parse and evaluate the various points of view being offered. In what follows, we will outline the issues at hand objectively: first providing a brief overview of federal and state pesticide regulations and how they pertain to cannabis; addressing claims of whether pesticide usage is “safe” or not; and, finally, offering our opinion of how the cannabis industry should address the pesticide conundrum considering the current regulatory environment and the state of our knowledge.

Before diving in, we are also aware that there is controversy around cannabis testing methodologies, and that the reliability of cannabis testing labs in general has been called into question by a number of the companies that have faced recalls. While we cannot comment on the operations of particular labs, we do support the application of consistent standards, proficiency evaluations, and stringent regulatory oversight to testing labs themselves, so that their results can be assured of being beyond reproach.

Still, 3C’s stance is that quality cannot be tested into a product. To have growers continue to produce contaminated cannabis only to see it recalled repeatedly is unsustainable for the industry; indeed, it threatens its very existence, as we discuss below. That is why we focus in this paper on the cultivation of the plant, as correcting problems on the production side is the only way to ultimately resolve the dilemma in which the industry finds itself.

Pesticide Regulation in the US Relative to Cannabis Cultivation

Cannabis’ pesticide problems stem in large part from the fact the pesticide regulation takes place at the federal level, under the auspices of the EPA. All pesticides undergo years of research and development before they can be sold to farmers and employed on crops. That research addresses questions such as where and how a pesticide can be employed, on what crops, in what concentrations, with what frequency, and how long before harvest can a pesticide be applied. Questions of worker safety are also addressed, such as those concerning what Personal Protective Equipment (PPE) might be required and how long workers must avoid treated areas (Re­Entry Intervals), among other concerns.

The fruits of such studies are then distilled to the contents of a pesticide’s label, which must be registered with and approved by the EPA before a pesticide can be distributed for sale. Federal and state laws require that pesticides be applied according to label directions, making the label a legal document of sorts. “The label is the law,” is a phrase common among agricultural professionals with which the legal cannabis industry is becoming acquainted.

The sticking point in regard to cannabis is that, due to its federal illegality, no research has been performed on the use of pesticides on cannabis. Due to the lack of research, no pesticides registered currently with the EPA are labeled for use on cannabis. Since all pesticides must be applied according to label specifications, this essentially prohibits pesticide use in cannabis production. However, some labels are written in such a broad manner that the use of those pesticides could not be construed as a breach of the legally­ binding use directions. Additionally, certain pesticides are of such low­toxicity that the EPA has deemed that their registration is not required; these are known as minimum­ risk products under section 25(b) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). At this time, the Colorado Department of Agriculture (CDA), in an attempt to offer guidance to cannabis growers, is maintaining a list of such products that, either due to broad label language or 25(b) status, may be used on cannabis without that use being a violation of the label.

Are Pesticides Safe for Use on Cannabis?

Since the first plants to be quarantined after discoveries of improper, off­-label pesticide use to the most recent recalls, some of the Colorado cannabis companies caught up in those enforcement actions have made public statements claiming that their products are safe. These statements are dangerously misleading, as they do not take into account the issues laid out above, nor the facts that follow.

Frequently, attempts to justify such claims point out that pesticides are employed on our food and therefore must be okay to apply to cannabis as well. This is a classic case of comparing apples to oranges; or, in this case, comparing apples and oranges to cannabis. Such data cannot be bridged for the simple reason that apples and oranges (and most other agricultural food crops) are not smoked. Smoking remains the primary method of cannabis ingestion, but cannabis products are also vaporized (concentrates), consumed (edibles), applied to the skin (topical creams and patches), and taken sublingually (tinctures, sublingual strips).

As noted, the studies that pesticides must undergo prior to being approved by the EPA involve measuring acceptable residues based on the method of consumption of the final product. Since most food is consumed and digested, few pesticides on the market have undergone pyrolysis studies, which examine how the chemical structures of pesticides degrade when burned. This means that while the fungicide myclobutanil, the active ingredient in Eagle 20EW, may be approved for use on grapes, that approval is meaningless in regard to cannabis, as grapes are not smoked and the relative safety of myclobutanil residues was not tested in regard to such a consumption method.

While studies may eventually reveal that certain pesticides may be used on cannabis without ill effects to the end users, such research has not been performed and no one can say with certainty what the effects of consuming cannabis containing pesticide residues might be. Even the CDA qualifies the list of products that may be used without violating labeling guidelines with the following statement, “These products have not been tested to determine their health effects if used on marijuana that will be consumed and thus the health risks to consumers is unknown.”

Again, no one can currently say what pesticides, if any, can be safely employed on cannabis; anyone claiming definitively that their products are safe despite off­-label pesticide use is making a statement that at this time lacks any scientific basis whatsoever.

Another claim made numerous times by companies defending their off­-label pesticide use is that no one has yet fallen ill from pesticide use on cannabis. While this is true, we must remember that we are in uncharted territory, and no large­scale public health studies have been done to determine what, if any, effects result from consuming cannabis to which pesticides were applied. We hope that no ill effects will surface, but the fact of the matter is that chronic health issues may take years to show themselves and a public health crisis may yet emerge.

Recommendations for the Cannabis Industry

We are advocates for cannabis legalization and want to see this industry grow and develop into one that is beneficial for all involved. We believe that cannabis can continue to be a force for positive change in numerous areas of society, from medicine to criminal justice to agriculture, and beyond. But, in order for it to do so, we must navigate issues such as those around pesticide use in an intelligent and responsible manner.

Our primary recommendation should be preceded by the statement that the use of chemical pesticides of the type triggering Colorado’s recalls is not needed in cannabis production. We make this statement based on years of experience working in, managing, and advising cultivation operations of all types, methodologies, and scales on how to grow successfully without illegal pesticides. Cannabis has survived and flourished throughout human history without pesticides, and will continue to do so if we cultivate it correctly.

As such, we recommend that growers n​ot​ employ any pesticides in a manner that violates label directions, and only use 25(b) products that have undergone pyrolysis testing to ensure that they are not releasing harmful compounds when burned. Furthermore, applications should only be made during the vegetative stage, prior to the emergence of flowers. Overall, if there is any doubt as to whether a product or material is safe, it should not be used until legitimate, peer­-reviewed research has been performed by a reputable institution.

Successful pest control can be achieved via intelligent facility design, robust environmental controls, workflow protocols, and strict cleanliness standards, in addition to preventative applications of appropriate minimum­ risk pesticides. There is no magic bullet that will solve all pest problems, which is why experienced agricultural professionals rely on Integrated Pest Management (IPM), defined as “an ecosystem­-based strategy that focuses on long­term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.” Overall, the adoption of Good Agricultural Practices (GAP) is much needed in the industry, and cannabis growers should look to agricultural operations that promote the four pillars of GAP standards (economic viability, environmental sustainability, social acceptability, and safety and quality of the final product) for guidance in formulating best practices in this new field.

This recommendation is not simply a matter of principle, but one that will preserve your business. In addition to costly and brand­-damaging recalls, we have already seen the first product liability lawsuits filed last year against LivWell by cannabis consumers over off­label pesticide use. Another issue is that of worker safety. Most cannabis cultivation takes place indoors, where pesticide residues can linger in garden areas and on equipment, creating toxic work environments. Unfortunately, based on the widespread nature of pesticide use in the legal cannabis industry, we feel confident in stating that thousands of workers employed in legal cannabis cultivation operations have applied chemical pesticides without proper PPE or safety training. Businesses employing pesticides off­-label will likely find themselves subject to liability claims from workers, as well as consumers, in the relatively near future.

Conclusion

In closing, the bottom line is that applying pesticides off­-label is a violation of state and federal law and could result in criminal and civil sanctions, should regulators and affected parties choose to pursue them.

It must also be noted that off­-label pesticide use threatens the industry as a whole. Point six of the Cole Memorandum states that the federal government will not make the enforcement of the Controlled Substances Act a priority as long as the “exacerbation of (…) public health consequences associated with marijuana use” is prevented. The emergence of a public health problem would be a violation of the Cole Memo ­and it could be argued that the current situation unfolding in Denver is already a violation ­ and could trigger federal intervention against states that have legalized cannabis. In this light, the Denver Department of Environmental Health, which is driving the recalls, has not “launched a campaign against legal cannabis,” as a company recently subject to a recall claimed, but is actually acting as a bulwark against a potentially serious Cole Memo violation that could shutter the entire industry.

Based on the current situation, the cannabis industry must come together to denounce and eliminate off­-label pesticide use. In order to ensure the health of patients, consumers, workers, and the industry itself, we must seize this opportunity to grow without chemicals that are currently illegal, potentially very harmful, and ultimately not even necessary.